 body {
    margin: 0;
 }

 .nav {
    position: fixed;
    top: 0;
    width: 100%;
    left: 0;
    height: 80px;
    border-bottom: 1px solid #f0f0f0;
    box-shadow: 2px 2px 5px #333;
    background: #fff;
 }

 nav {
    width: 990px;
    height: 80px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
 }

 nav a.logo {
    display: inline-block;
    width: 150px;
    height: 50px;
    background-image: url("../京东狗.png");
 }

 nav div {
    color: #f0f0f0;
 }

 nav div a {
    color: #ff0000;
    text-decoration: none;
 }

 .reg {
    width: 330px;
    height: 700px;
    margin: 0 auto;
    margin-top: 300px;
    display: flex;
    flex-direction: column;
    justify-content: space-around;
    align-items: center;
 }

 .reg div {
    width: 320px;
    height: 60px;
   display: flex;
 }
 .reg div label{
   display: inline-block;
   min-width: 98px;
   height: 48px;
   text-align: center;
   line-height: 48px;
   border: 1px solid #f0f0f0;
   color: #666;
 }
 .reg div input{ 
   height: 50px;
   flex-grow: 1;
   line-height: 48px;
   border: 1px solid #a0a0a0;
   outline: none;
   border-left: 0;
 } 
 .reg div:nth-child(2) input{
   width: 120px;
 }
 .reg div .send-code{
   display: inline-block;
   min-width: 98px;
   height: 48px;
   text-align: center;
   line-height: 48px;
   border: 1px solid #f0f0f0;
   color: #666;
   border-left: 0;
 }
.reg .protocol{
    line-height: 50px;
    font-size: 14px;
    justify-items: first-start;
    text-align: left;
}
.reg .protocol input{
   width: 16px;
   height: 16px;
   margin: 17px 4px;
   flex-grow: 0;
}
.reg .protocol a{
   text-decoration: none;
}
.btn-red{
   background-color: red;
   color: #fff;
   font-size: 22px;
   display: flex;
   justify-content: center;
   align-items: center;
}